During the past five years more progress has been made in clarifying the chemistry of the red pigments of human hair and chicken feathers than in 50 years of chemical research on black melanins. This progress was largely due to the brilliant work of Prota, Nicolaus, and their co-workers.1-3 Identification of the chemical structure of the nonprotein ("red melanin") part of these pigments shed light on many heretofore unexplained aspects of pigmentation in red animals. The day is far away when Sorby, the discoverer of the "pink constituent" of human red hair, could write: "The presence of the substance cannot have any material influence on the general tint"4; and it seems ludicrous that a mere 17 years ago the very existence of these substances was questioned5 and this challenge uncritically accepted in the dermatologic literature. From our own work the concept has emerged that the red pigmentary